A common example of a digital camera with panning and/or tilting functionality is a web camera, which e.g. may be mounted at a given location for the purpose of surveillance, production monitoring, etc. The web camera comprises an optical input in the form of a lens or objective and an image capturing unit for producing a digital image from light received from the optical input. Usually, the image capturing unit comprises a CCD element (Charge Coupled Device). The web camera has software and hardware for allowing the camera to be connected to a given network, such as an Ethernet or Token Ring network. The web camera is arranged to produce digital images at a given rate, such as 1-25 images per second. In order to increase the visual volume covered by the web camera, the camera is provided with mechanical means for panning and/or tilting the camera. Generally speaking, “panning” means rotating the camera by a given angle (normally 0°-360°) in a horizontal plane, and “tilting” means rotating the camera by a given angle (normally 0°-180°) in a vertical plane.
In prior art web cameras the panning and/or tilting functionality is obtained by moving the whole camera or at least the objective thereof. Since the camera and objective have a considerable weight, such an approach involves complex, large and expensive mechanics. Furthermore, the speed at which the camera may be panned or tilted is restricted due to the large mass, that has to be moved accordingly.